Heidi McBride: Mitochondria are well connected

A t the mention of mitochondria, do you visualize little lozenge-shaped organelles that sit passively in the cytoplasm, quietly brewing up ATP and only getting to do something exciting after being enlisted in an apop-totic cascade? That image, comforting though it may be, is woefully incomplete. In fact, says McGill University's Heidi McBride, mitochondria are highly dynamic organelles that form an extensive network in the cell and that react to alterations in cellular homeostasis with dramatic physiological and morphological changes (1, 2). She should know, because she's studied mitochondrial biology since the start of her career (3), and her work has helped change the way other scientists view the organelle. McBride's lab has also shown that mito-chondria are intimately connected to other organelles and to membrane traffi cking pathways (4–6). Her group is currently exploring how these connections might impact phenomena as diverse as neuro-degeneration and heart disease, she told us when we spoke with her recently. How did you decide to pursue a career in science? In high school I played a lot of music— saxophone, clarinet, flute, and piano— because I had to cover a lot of instruments in different stage, symphonic, and jazz bands. My music teacher encouraged me to go to McGill because of their music program, and I almost decided to study music when I went there for university. But I'd loved my science classes in high school, too. I remember being especially interested when we started to learn about photosynthesis because I grew up on a farm and it was fascinating to me how plants could make fuel from sunlight. I decided there would probably be more jobs in science, so I majored in biochemistry. As an undergraduate I did lab work with John Bergeron, who is a cell biologist here at McGill. Then I ended up doing my PhD with Gordon Shore, who was a good friend of John Bergeron's, because the things he had taught in my classes about mitochon-drial protein import and the biogenesis of organelles had really caught my interest. My marks in school were never great, but Gordon was a farmer and knew I grew up on a farm, so I guess he hired me because he thought I'd work hard. [Laughs] My main claim to fame in graduate school was the work I did showing that the transmembrane domains of some mito-chondrial proteins can function as signal anchor …